The couple, who married in 2005, have three of their own children: Henry, Johan, and Lou. Klum also has a daughter, Lenni, from a prior relationship.

Seal said that the song references one of their children.

"There's a chapter in that song that is directly related to our first child, Lenni," he said. "But I try not to be too specific because it takes away the ability for people to relate and make it their own."

The couple clearly doesn't have a problem disrobing; Klum told InStyle magazine in Janaury that they keep nude photos of themselves in their bathroom at home.

"They see their parents naked all the time," Klum said in reference to her children. "We are not ashamed."